Generally, exercise devices provide a framework for individuals to strengthen and stretch various muscle groups. Devices that assist users in targeting their abdominal muscle groups have been especially popular over the past few decades. One difficulty associated with marketing an exercise device—especially one targeted at abdominal muscles—is that a device that provides only one or two possible exercise movements can quickly become unused by the purchaser. One reason for this is that the user develops muscle memory: after a few weeks of training with a single exercise movement, the user's muscles targeted by that particular exercise become stronger and are better able to perform that movement. As a result, the user feels that the exercise movement is no longer strenuous enough. The user is likely, at that point, to discontinue use of the exercise device.
Many exercise devices, therefore, lack the features and functionality to continually challenge users' fitness. For example, to the extent that most devices employ resistance forces to increase the difficulty of an exercise movement, that resistance cannot be readily varied to adapt to the strength of the user. Also, most devices facilitate only a single exercise movement, which, as described above, quickly becomes boring. Finally, many known devices are relatively bulky, heavy and difficult to store in small storage areas.
Accordingly, a need has developed for a low-cost, portable exercise device that provides easily variable resistance for one or more exercises. What is also needed is an exercise device that facilitates a number of beneficial exercise movements that target multiple muscle groups and/or a muscle group in a variety of useful ways. Further, there is a need for such exercise devices to be easy to manufacture, assemble, use, and store in a small space, as well as that they be safe to use.